ijoists for soffits

tsandJanuary 13, 2008


Planning on starting a DIY basement remodel. I am planning to do the DIY stuff and and GC'ing the items I don't want to do.

I am planning the insulation and framing phases and I have 2 questions:

1. Has anyone used I-joists (engineered wood joists) to build the HVAC/Plumbing/electrical soffits? It seems it would be way easier than using stick lumber or metal framing. Any details or pictures on how it worked or didn't work would be appreciated


2. Has anyone recently used Foamular or other XPS (Extruded Polystyrene Foam) sheets to insulate their basement? I understand that some local building inspectors don't like XPS glued on the walls? Any details or pictures on how worked or didn't work would be appreciated.

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I joists are structural. It's way overkill for building bulkheads to hide HVAC etc. It would seem a lot easier to knock together 2x2s or 2x3s.

XPS adhered to the walls is an excellent way to insulate a basement. Adhesive only works well on unit masonry walls, such as block. There are typically too many irregularities in a poured wall for it to hold. In that case, use mechanical systems--such as concrete screws through fender washers. Ideally, seal all joints with tape and use foam where necessary to ensure that as little air as possible is able to circulate between the foam and the foundation wall.

Here is a link that might be useful: Building Basements

    Bookmark   January 13, 2008 at 12:18PM
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